Arrangement for braking the picker stick of a loom

ABSTRACT

The present invention relates to an arrangement for braking a picker stick of a loom which comprises an elastic element which is compressed upon the braking of the picker stick.

United States Patent 1191 1111 3,782,423

Lutz Jan. 1, 1974 1 ARRANGEMENT FOR BRAKING THE [56] References Cited PICKER STICK OF A LOOM UN1TED STATES PATENTs [75] Inventor: Friedrich Lutz, Durnten/Zh, 798,860 9/1905 Allen, Jr. 139/166 Switzerland 973,132 10/1910 Northrop 139/166 2,972,360 2/1961 Renther et aL. [39/166 1 Asslgneel Machmery Works 3,005,471 10/1961 Renther et a1. 139/166 fiigs g FOREIGN PATENTS OR APPLICATIONS 23,467 1911 Great Britain... 139/166 [22] Flledl 10, 1972 414,492 12/1966 Switzerland 139/166 21 Appl. No.2 279,395 Prima Examiner-James Kee Chl "y Att0meyD0na1d D. Denton [30] Foreign Application Priority Data Aug. 31, 1971 Switzerland .1 12753/71 57 ABSTRACT The present invention relates to an arrangement for braking a picker stick of a 100m which comprises an I 58] Fie'ld 6 167 168 elastic element which is compressed upon the braking ,l39/,l6l S, of the picker Stick.

4 Claims, 2 Drawing Figures ARRANGEMENT FOR BRAKING THE PICKER STICK OF A LOOM Such arrangementswith different types of elastic elements are known. They have the disadvantage that the elastic element is stressed beyond its elastic range upon varying operating conditions and thereby becomes soft and it is compressed to too great an extent. Therefore, its shape and properties are changed, as a result of which the impact of the picker stick becomes hard and damage to the element furthermore occurs.

The object of the present invention is to avoid these disadvantages. The invention is characterized by the fact that a second elastic elment of plate-like shape at one of two opposite end parts rests against a fixed stop and at its other end it bears the elastic first element, and that the second element is imparted elastic deflec'- tion by the forces occurring upon the compression of said elastic first element.

The arrangement of the invention accordingly has the advantages that a hard blow cannot occur since the elastic first element is so arranged on the second element that it yields and therefore cannot be overstressed. Destruction of the elastic first element by the picker stick is thus avoided. The force for the braking of the picker stick can furthermore be imparted a characteristic favorable for the existing conditions by a suitable shaping and selection of the material of the two elements and of the stop. In particular, the progressively increasing braking force desired can be obtained in this arrangement, which in order to reduce the noise formed should be weak at the start. The arrangement is furthermore characterized by great simplicity and permits optimum utilization of the space available. Finally, it has the advantage that said first element accurately retains the position which has been given to it even after a lengthy time of operation.

The invention will now be explained in further detail with reference to preferred embodiments and to the drawing thereof, in which:

FIG. 1 is a view of an arrangement for the braking of a picker stick, and of its position on the loom, seen from the front, and

FIG. 2 is a view ofa second embodiment ofa braking device.

In both figures identical parts have been provided with the same reference numerals.

Referring to FIG. 1, shuttle 11 is propelled by a picker stick 12 from right to left along the lay beam 13. After the shuttle 11 which comes from the left has struck the picker or the picker stick 12, the latter is held and braked by the bumper 14. Conversely, when, by actuation of the lug strap 15, the picker stick 12 is moved to the left in order to drive the shuttle 11, it is again brought to a standstill by a braking arrangement 20.

The braking arrangement consists of an elastic first element 21 of U-shaped construction whose outer surface is provided with a piece of leather 22 in order to protect it against wear. A second element 23, which may be plate-shaped-in constructiomhas its one end 28 fastened by the bolt 26 to the stationary stop 24. The first element 21 is operatively connected to the free end 29 of the second element 23. The second element 23 also consists of elastic material and has the shape of an elongated plate which'extends in the vertical direction from its attachment to stop 26 and has operatively connected to it the first element 21 in the form of an upright U.

In the operation of the loom, the shuttle 11 coming from the left strikes the picker of the picker stick 12. In this way the latter is knocked against the bumper 14 and braked by the latter, whereby the shuttle 1 1 is also braked. Upon the reverse process, ie upon the driving of the shuttle 11 towards the left, the picker stick 12 is moved vigorously towards the left by means of the lug strap 15. After the shuttle 11 has thereby been brought to the desired speed, the picker stick 12 is again brought to a stop by striking against the braking arrangement 20.

In this connection, it strikes against the first element 21 and, due to its U-shaped construction, is thereby compressed. In this way it exerts a force on the second element 23 which is also elastic. As a result of the force transmitted from the first element, the upper end part 29 of the second element 23 is moved towards the left until the picker stick has come to a stop. The path of travel of the upper end 29 of the element 23 towards the left amounts on the average to about 1 cm. When the elements 21 and 23 are made of elastic material, the advantage is obtained that a relatively large amount of energy is converted into heat and the picker stick 12 therefore does not rebound excessively from the braking arrangement 20. Rubberized fabric and the like have proven to be advantageous for use as elastic material for the first element 21 and second element 23.

The embodiment shown in FIG. 2 differs from that shown in the braking arrangement of FIG. 1 by the fact that the stop 25 (designated 24 in FIG. 1) extends towards the other free end 29 of the second element 23, and that the surface 27 facing surface 30 of element 23 is curved upwardly and outwardly therefrom. The adjacent faces30 and 27 of the element 23 and stop25, respectively, thus move away from each other. In this embodiment, the second element 23, upon the braking of the picker stick 12, comes to rest with an increasing area of contact of its surface 30 against the surface 27 and is thus buffered by varying amounts as the adjacent faces progressively contact each other. It is clear that with an increasing deflection of the element 23, the lever arm which this element 23 forms becomes shorter. The braking or stopping force increases corresponding to this shortening. Furthermore, during the entire duration of the stopping process in this embodiment, the second element 23 is elastically stressed in its entirety, while in the embodiment shown in FIG. 1, the elastic deformations are concentrated in the region of flexure which is formed or located at the height of the upper end of the stop 24.

It also lies within the scope of the present invention for the second element 23 to be rigid and to be pressed, for instance, by a tension spring arranged at the place of the bolt 26 against the surface 27 so that upon impact of the picket stick, it rolls along the surface 27. The embodiment shown in FIG. 2 has the following advantages over this:

A spring results in a higher storage of energy than in the case of a piece of elastic material. When a piece of elastic material is used for the second element 23, a weaker rebound of the picker stick 12 is thus obtained.

Since the picker stick l2 participates in the movement of the lay and the braking arrangement 20 when it acts as bumper is fastened to a stationary part of the machine, the first element 21 must move togetherw'ith the picker stick 12 for the interval of time during which the picker stick l2 and the first element 21 are in mutual contact. This can take place much more easily if the second element 23 consists of a piece of elastic material.

An embodiment in which the second element 23 is elastic and of curved shape also lies within the scope of the present invention. In this case the plate-shaped second element 23 is developed curved away from the stop 25; thus in FIG. 2 it would be curved to the right. With the second element curved in this way, the surface 27, on the other hand, can be made flat and vertical.

It will be appreciated that many different types of materials may be used to impart a buffering or braking effect on the picker stick by providing elastic-like quality to the function of the first and second elements.

The brake arrangement in accordance with the invention can also be used instead of the bumper 14, Le, it can also be used for the braking of the shuttle 11 when it has come from the left and has struck the picker or the picker stick 12 (see FIG. 1).

it will be appreciated that various changes and modifications may be made within the skill of the art without departing from the spirit and scope of the invention illustrated herein.

What is claimed is:

l. Arrangement for braking of a picker stick of a loom which comprises a first element compressible by bending upon the braking of the picker stick; an elongated second element bendable by deflection, said second element having its one end connected to a fixed stop and its other end free and connected to and carrying said first element; said second element providing an elastic bendable deflection of its free end due to the forces applied to said free end by the compression of said first element by said picker stick.

2. Arrangement according to claim 1 in which said stop extends towards said free end of the second element and that the adjacent surfaces of said stop and said second element diverge towards said free end so that the second element is bent towards surface of said stop by the forces occurring upon the compressing of said first element.

3. Arrangement according to claim 2 inwhich said second element consists of an elongated piece of elastic material and that the surface of said stop which is adjacent to the surface of said second element is curved away from the free end of said second element, the adjacent surface of said second element being pressed by varying amounts against said curved surface of said stop by the forces applied to said first element.

4. Arrangement according to claim 3 in which said first element is made of an elastic material and is of U- shaped construction and that it is in the shape of an upright U operatively connected to said free end of said second element. 

1. Arrangement for braking of a picker stick of a loom which comprises a first element compressible by bending upon the braking of the picker stick; an elongated second element bendable by deflection, said second element having its one end connected to a fixed stop and its other end free and connected to and carrying said first element; said second element providing an elastic bendable deflection of its free end due to the forces applied to said free end by the compression of said first element by said picker stick.
 2. Arrangement according to claim 1 in which said stop extends towards said free end of the second element and that the adjacent surfaces of said stop and said second element diverge towards said free end so that the second element is bent towards surface of said stop by the forces occurring upon the compressing of said first element.
 3. Arrangement according to claim 2 inwhich said second element consists of an elongated piece of elastic material and that the surface of said stop which is adjacent to the surface of said second element is curved away from the free end of said second element, the adjacent surface of said second element being pressed by varying amounts against said curved surface of said stop by the forces applied to said first element.
 4. Arrangement according to claim 3 in which said first element is made of an elastic material and is of U-shaped construction and that it is in the shape of an upright U operatively connected to said free end of said second element. 